Reducing mechanism.



A. A. DAY. REDUCING MECHANISM. APPLICATION FILED mm: 19, 1907.

91 9,327, Patented Apr. 27, 1909.

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KQYZW im) M I Aflowzeyp d MMQQK NVENTOR A. A. DAY. REDUCING MECHANISM.

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NE a INVENTOR /2 h A Patented Apr. 27, 1909.

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I have foundby practical experiment that ALBERT A. DAY, OF NEW; YORK, N. Y.

REDUCING MECHANISM.

specification of Letters Patent.

Patented April 27, 1909.

Application filed June 19, 1907. serial No. 379,786.

'To all, whom it may concern:

Be it known that I, ALBERT A. DAY, citizen of the United States, residing in the borough of Brooklyn, in the count of Kings and city and State of New Yor have mvented certain new and useful Improvements in Reducing Mechanism; and I do hereby declare the following to be a full,

clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same. v

My invention consists in the novel features hereinafter described, reference bein had to the accompanying drawings which ustrate one form in which I have contemplated embodying the invention and said invention is fully disclosed in the following description and claims.

' The object of my invention is to provide asatisfactory reducing mechanism for the purpose especially of reducing. and feeding fuel, such as lignite and soft or bituminous coal in a finely divided condition to a boiler furnace, although the apparatus hereinafter described may be used in treatment of other it is very diflicult to insure the uniformity of fineness of the powdered fuel, or other material, which is delivered from a reducing mechanism owing to the fact that the larger and heavier particles find their way by gravity or otherwise into the discharge of the apparatus.

It isone of the objects of my invention to arrange in a vertical relation a-= preliminary reducing mechanism, a pulverizing mechamsm below and in communication therewith and a grinding mechanism below the pulverizing mechanism, and to provide an e lector fan connected with the apparatus a ove the pulverizing mechanism.

I also provide means for admitting air to the apparatus at the bottom and thus create by means of the fan an upward suction, which tends to draw into the fan all the lighter particles from the reducing mechanism, the pulverizing mechanism and the grinding Inecl1 anism, so that only the heavier particles of the material will pass downward throu h the machine. lhus the material when it leaves the preliminary reducmg mechanism and drops into the pulverizing mechanism conmovementwill cause it to be tains some fine dust articles, and these are sucked at once into tl fe fan, and do not go to the vpulverizer; the heavier particles pass to the pulverizing mechanism and so much of this ortion of the material as is converted by t e pulverizing mechanism into dust of such fineness as to be carried bynthe suction of air will be caught up and taken to the fan, leaving only the heavier particles to pass onto the grinding mechanism which there fore has to treat only a small part of the material. The grinder reduces the larger particles to powder which is caught up in the air currents and carried to the fan. Any material esca ing from the grinder is conveyed to the pre iminary reducing mechanism and again passed through the. machine. It will, therefore, be seen that instead of passing all the material through all the the apparatus, I separate after each reduction, all the lighter particles, removing them from the apparatus and only the heavier particles are passed through more than one reducing mechanism. This effectsan immense saving of power and greatly increases the effectiveness of the apparatus. By regulating the speed of the fan I can regulate the power of the air draftor suction and to a large extent control the maximum size of the particles which will be carried to the ejector fan.

I also providea grinding mechanism of novel construction, comprising a horizontal revoluble lower grinding 'member, above which is a horizontally disposed u per grinding member, supported by vertica ydisposed pendulous connections or links, which permit aslight rotary movement of the upper member. The upper member is suspended by its connections so that it just clears the lower member, and when the material to be treated is between the two members, the rotation of the lower member will cause the attrition or grinding thereof between the grinding members. The frictional resistance on the lower face of the upper grinding member, will cause it to revolve slightly withthe lower member, and such slight revolving lifted slightly, by reason of the inclination of the suspending connections. This construction will, therefore, produce a compensating action by means of which the pressure and friction on the material between the faces of the upper mechanisms of and lower members will be maintained practically constant as will be readily understood. I

I also provide an auxiliary weight or weights for the upper grinding member which can be attached thereto as the member itself wears to add weight to compensate for the loss by wear, and I also provide means for adjusting the members withrespect to each other, preferably by making the suspending connections adjustable to secure the proper relation between said members at all times.

In order that the finely ground material may rise from the grinding members and pass off to the fan with the currents of air, I

' provide the upper grinding member, which is preferably annular in its general form, with s aces arranged at intervals through which tlie fine particles may rise. 7

.My invention also includes certain details which are fully described hereinafter.

Referring to the accompanying drawings, Figure 1 represents a vertical sectional view of a reducing apparatus embodying my 1nvention and adapted for use to reduce fuel such as lignite and soft coal to a powder and feed the same to a furnace. Flg. 2 represents a horizontal sectional view of the same. Fig. 3 is a detail perspective View of the upper grinding member of my lmproved grinding mechanism.

In the drawings A represents a vertically disposed casin open at the bottom, and formed prefera 1y of a plurality of built-up sections or rings a, a supported u on an annular base 0/ provided with suita le legs of. The rings. a. are wider than rings a and project inwardly beyond the same, and the upper portion of the casing is preferably formed by alternating the rings a and a, as shown, while the low'er part is formed of rings a only.

Superposed upon the. casing'A is a casting provided with a hopper B, and an annular fan casing C, having an annular slit or aperture c communicating with the casin A, and havin a tangential discharge 0 whic 1 is connected by a pipe with an aperture in a furnace door (not shown) when the apparatus is used as a fuel feeder. The top casting, the rings a a and base a. are united by suitable bolts 0. making a strong and convenient structure as shown. I may, however, construct the apparatus in a different manner if desired.

D represents a vertical revoluble shaft whichextends through the casing and hopper and is provided at its lower end with a step bearing (1 permitting a certain amount of in; clination of the shaft, and the shaft is provided at the top with a steadying bearing (1 carried by a spider or frame (1 secured to the hopper B, and fitting the shaft loosely, a su cient amount of play being provided in said steadying bearing, to permit the shaft to rotate gyroscopically upon a free axis,

together with the parts carried thereby so that it will come into a state of stable equilibrium when rotated athi h speed, after the manner "of a top, and i1 rotate then only upon the step bearing, and without touching the up er or steadying bearing. Any form of step earing which will permit of the gyroscopic rotation of the shaft and its connected parts, may be substituted for the simple form of step herein shovm.

The hopper B forms part of the preliminary reducing mechanism and is 'rovided with radially disposed webs b to ho d the material from rotation and below said Webs, the hopper is provided with an annular pocket or recess b. This ocket will naturally fill up with comparatively finev articles. of the mateiial and will form a cus 'oninto which any mounted on the shaft D to rotate therewith and is adjustable vertically therein. 'lhe cone E with the hopper B forms the preliminary reducing mechanism. The shaft D is preferably square (or of other poly onal shape) in cross section and the cone I i fits upon said shaft and projects into the hopper B. In this instance the shaft is shown provided with a rigidly secured collar externally threaded and engaging an internally threaded ring e, which supports the cone, and by adjusting the ring c with respect to collar e,

the cone may be raised and lowered in the hopper and thereby the space between the cone and the delivery aperture of the hopper may be regulated or adjusted. This will re ulate the fineness of the larger particles de 1vered by the preliminary reducing mechamsm into the casing below. The shaft D also carries arms f, below the cone E, which extend into the fan casin C and are provided with fan blades F. Befow the fan arms f,

the shaft D is provided with a series of smaller disks 9, a ternating with larger disks 9, the latter of which carry pulverizing or lmpact rods g -extendmg thereform into the recesses formed between the inwardly proectmg wings a of the casing and said casing rings a are provided with inwardly extendmg stationary impact rods g which extend into the spaces between theprojecting disks 9, as shown. In this instance the rotary impact rods and stationary impact rods form refractory substance,.as' a iece. of rock or the pulverizing mechams m, below which is located the grinding mechanism, which is preferably of the form herein shown and described.

H represents the lower grindin member which consists of a disk having a horizontal u per face, mounted on shaft D, to rotate t erewith and forming the bottom of the casing A. Above the disk H is the upper grind- I .ing member H which is annular 1n general form, and is preferably formed in two parts each of less extent than half of the annulus, the said parts being rigidly connected, and leaving openings i between their adjacent ends to permit the finely ground material or dust to rise. I conveniently form the upper grinding member casting the same and at thesame time umtlng the sections thereof,

by placing the headed connecting bolts or bars h h in the mold, before the metal is poured, thus, rigidly uniting the parts as shown in Figs. 2 and 3. The lower, face of the upper grinding member is flat, and the upper face is inclined downward toward its inner edge, so as to direct material falling thereon into the center. The upper member H is provided with means for attaching it to suitable supporting connections, in this'instance ears or perforated lugs k and I prefer to provide four or more of such ears, although a smaller number may in some cases be suflicient. The member H is su ported by means of" pendulous vertically disposed connections it from a stationary part of the casing A, as shown, so as to nearly touch the lower grinding member H. It will be seen that when material is between the members H and H and the lower member H is rotating the friction on the lower face of the upper member will tend to cause it to slightly move in a rotary direction with the lower member and such movement will more or less raise the upper member, according to the greater or ess inclination of the connections 712, which connections will also resist the torsional movement. T his will cause the upper grinding member to bear upon the material-under treatment with a substantially constant pressure and-friction, and the construction provides a compensating means for maintaining the pressure and friction practically constant. 1 bus if the friction is momentarily increased for any reason, the upper member will instantly be swung farther around tor sionally, thus reducing the friction correspondingly. If the friction is momentarily reduced the upper member will swing back slightly and increase the friction, as will be readily understood. It will be understood that whenever the a paratus is in operation and there is materiai between the upper and lower grinding members, there will be a certain amount of torsional drag on the upper members, which distorts the connections h out of their normal positions. In order to facilitate the introduction of the material between the upper and lower members H and .H', I prefer to curve or bevel the lower and inner edge of the upper member H all. the way around as shown at h and also to bevel or curve the forward ed e b of each section v of said upper member, as shown in Fig. 3.

I also provide means for securing an accurate adjustment of the grinding memberswith respect to each other. I have shown the connections h? provided with turn buckles h to enable them to be adjusted at any time, and the casing A is provided with hand holes atto enable the adjustment to be made from time to time to compensate for wear. its the upper member H wears away it will also lose its weight and in order to compensate for this loss, I rovide auxiliary weights H as shown in igs. 1 and-2, preferably having slots therein to slip over the ears k which weights may be added as required to make up for the lossof weight.

L is a trough located beneath the lower part of the casing and adapted to catch any material which may fall from the grinding mechanism and convey (see Fig. 1) which carries it upward and discharges it by means of a trough m (partly broken away in Fig. 1) to the hopper it the same time it may be noted that when the fan is in operation, there will be a suction of air all around the grinding mechanis between it and the casing 11, so that no fine material will be likely to i all out of the cas- 1n 'Ihe shaftD is driven in any suitable ma. nor, as by a pulley D at its lower end, secured thereto frictionally so as to slip in case of any stoppage of the rotary parts, and the shaft is preferably bored throughout its length to provide an oil passage d communicating with an oily cupd at its upper end for lubricating the step bearing.

In the operation of the apparatus, the material is fed into the hopper B, and acted on In this instance 7 it to an elevator M by the preliminary reducing mechanism, to

.fan casing and thecoarser particles will deys'cend and be acted on by the pulverizing mechanism, the finer particles so formed be ing continually carried upward by the air to the fan and the coarser particles falling into the grinding mechanism, in which they are finely reduced to an impalpable dust or powder, which is carried upward therefrom to the fan. The fine particles or dust are discharged by the fan, with air into the furnace, and will burn with the production of intense heat. V

What I .claim and desire to secure by. Letters Patent-is:-

1. In a reducing mechanism, the combination of horizontally disposed upper and lower grinding members, means for continuously rotating'the lower grinding member, a stationary support for the upper grinding member, above the same, pendulous connections secured :to' said support, and connected to said upper grinding member at a distance from its center, and constructed to permit 5 stantially as described.

2. In a reducing mechanism, the combination of horizontally disposed upper and lower grinding members, means for. rotating the 1' lower grinding member, a stationary support 1 for the upper grinding member located above the same, links connected to said support, and connected to the upper grinding member at separated points at a distance from its center, forming the .only'connections with said upper grinding meinber, and permitting said upper grinding member to turn on its own axis with respect to its support to alter its vertical relation with respect to the lower grinding member, and means for; positively adjusting said upper and lower grinding members, one with respect to the other, substantially as described.

3. In a reducing mechanism, the combination of horizontally disposed upper and lower grinding members, means for rotating the lower grinding member, a stationary support for the upper rinding member located above Y the same, linirs connected .to said support, and connected to the upper grinding member at separated points at a distance from its center, forming the only connections with said upper grinding member, and permitting said upper grinding member to turn on its own axis with respect to its support to alter its 'verticalrelation with respect to the lower grinding member, means connected with said links for positively adjusting said upper I and lower grinding members, one with re-' spect to the other, an auxiliary weight and means for securing said weight'to the upper grinding-member to compensate for wear, substantially as described. 4'. In a reducing mechanism, the combination with horizontally disposed upper and lower grinding members, said u per member. being a ertured to permit the nely ground materia to rise therethrough, means for driving the lower grinding member, a support for said upper member located above the same, pendulous devices extending fsrorns said sup ort, connected: to the upper grinding mem er at a distance from its center, and permitting relative movement in a rotary di rection of the upper grinding member with respect to its support; to change'the vertical relation of the upper and lower grinding members, a casing inclosing said grinding members, and provided with an outlet at its upper end, and means for creating a current of airfrom the'bottom of the casing to said outlet, to remove the finely divided material,

substantiallyas described.

5. In a reducing mechanism, the combination with a vertical revolubleshaft, a supporting bearing for "the lower end of said of avertica and commumcatlng therewith, pulverizing -mechan1sm located in the upper art of sald "part 0 said casing, a horizontally disposed connecting said -u connected with said having an annular aperture communicating shaft, a steadying bearing for the upper end of said shaft, provided with sufficient play to ermit the shaft .to rotate upon a free axis, a orizontally disposed lower grindin member carried by and rotating with sai shaft, a horizontally disposed up er grinding member independent of said s aft, and surrounding the same, a support for the u per grinding member above the same, an vertically disposed connections from said support secured to the-upper grinding member at a distance from its center, and constructed to permit a relative movement in. a rotary direction between said upper grinding member and its support to change its vertical position with respectfto the lower rinding member, substantially as. describe 6. In a reducing mechanism, the combination with a reliminary reducing mechanism, lly disposed casing located below casing, a horizontally dispose revoluble lower rinding member locatedin the lower upper grinding. member located above the lower grinding member, pendulous supports,

oer. member with parts V casing and constructed to permit movement of the upper grinding member in a rotary direction, to chan e its vertical relation with respect to the ower grinding member, an ejector fan casing located above the pulverizing mechanism, and

with said chamber, and a fan in said fan casing, substantially as described.

7. In a reducing mechanism, the combination with a rotatable grinding member and an opposed non-rotatable grinding member, supporting connections between said .nonrotatable member and a stationary part permitting a slight movement of the non-rotatable member in a rotary direction, said connections being so constructed that the said permitted movement will cause the separaof--the connected member in a rotary direction, to relieve the pressure between theopposed grinding surfaces, substantially as described.

9. In a reducing mechanism, the combination with'horizontally disposed upper and lower grinding members, means for rotating substantially as described.

I constructed to permit the upper member to move slightly in a rotary direction to relieve lower grinding members, means for rotating the lower grinding member, connections extending from the up er grinding member to a stationary part, ho ding the upper member I from rotating with the lower member but constructed to permit the upper memberto i move slightly in a rotary direction to relieve l the pressure between the grinding surfaces of l the members, the up er grinding member having its grinding surface recessed to afford space for the discharge of ground material,

10. In a reducing mechanism, the combination with horizontally disposed upper and the lower grinding member, connections eX- tending from the up er grinding member to a stationary part, ho ding the upper member from rotating with the lower member but the pressure between the grinding surfaces of the members, the upper grinding member being provided with apertures extending therethrough above the grinding surface of the lower grinding member to permit the ground material, substantially as nation with horizontally disposed upper and lower grinding members, means for rotating the lower grinding member, connections extending from the up er grinding member to a stationary part, ho ding the upper member from rotating with the lower member but constructed to permit the upper member to move slightly in a rotary direction to relieve the pressure between the grinding surfaces of the members, the upper grinding member consisting of separate horizontally curved parts, spaced a distance apart, and rigid connections between said arts, whereby apertures are formed througli the upper member for the escape of tially as described.

In testimony whereof l aflix my signature,

in the presence of two witnesses.

ALBERT A. DAY.

Witnesses:

L. P. WHITAKER, J. MooRE,

ground material, substan- 

